Art of coating sheet material



AprilvZl, 1942'.- j v E. c. HoMAN y v2,280,433

IART OF CO'ATING. SHEET MATERIAL Filed oct( 11; 1940 2 sherssneet 1 yINVEN R37 i www ATTORNEY.

Eirzz 62939272412) April 21, 1942.r E. C. HOMA'N 2,280,433

ART OF COA'ING SHEET'MATEWIAL Filed oct. 11, 1940 2 sheets-sheet 2INVENTQR.

ATTORNEY.

Patented Apr. 21, 1942 nnnunLlElLTATEs PATENT ori-ica 2,230,433 l Aa'roFcoA'rrNG snaar Marsman,

Edward C. Homan, yllast Ohrange, N. J., assigner to Irvington VarnishInsulator lCo., Irvington, N. J., a corporation of .New Jersey iApplication oetote 11, icio, serai No. 36am and spaced coating barswhich are additionally i claims. This invention relates tothe artortins' `,sheet material; and the invention hasreference,l

more particularly, to means for simultaneously applyingA single, uniformcoats of viscous liquid substance to opposite faces of moving sheet material; which coats may be either heavyor lighng that is of any desiredthickness'wltliinreascnahle ,A limits.

' Pursuant to heretofore known methods of epplying viscous liquidcoatings to sheet material,` it has been the practice to deposit theapplied coats to one or both faces of the material by `means of bluntknife-like elements or doctor plied, since the required strong tensionalcontact of the sheet material with knife or doctor blade edges precludeddeposit of a single heavy or thick coat. A heavy or thick coating couldtherefore only be obtained by building up, one upon another,successively applied thin coats; and such relatively disposed in acalculated vertically oil?-l sst reiation, whereby while the coatingthickness still controlled by the lateral spacing of the coating bars,the very,slight'verticaloifsctotthe transverse waves in the moving sheetmaterial which, if permitted to occur, would result in irregularity' inweight and thickness of the applied coating substance, and wouldconsequently produce non-uniform coatings.

Another object `oi? the invention is to provide coating bars which arerelatively exible, in combination with rigid supporting `or backingmeans therefor, including means whereby said coating bars may be locallyrelatively adjusted at desired points along the lengths thereoL'toassure accurate and uniform orice forming spacing thereof vthroughouttheir length, all to the end that equal pressure is Vsimultaneouslyexerted by the bags4 upon the coating substance andwthegmoidngs'eetmaterial, thereby toassure/ah established equiapplication of successivecoats rendered extremely /lbriumfin oppositely applied pressure thereofdicuitiienot altogether impossible, attainment of a comparatively thickcoating which would be uniform throughout its extent.

Having the defects of the above'mentioned old coatingmethods in view, itis an object of this invention to provide a method and means forapplying coats of viscous liquidsubstances to both sides or faces ofmoving sheet material,A whereby the applied coatingsmay be of desiredselected uniform thickness throughout, wherein the `coating substancewhen applied to A textile sheet material or cloth, especially one ofmore or less open weave, will be uniformly concentric to the threadsthereof.

Theinvention has for a further object to provide means for applyingcoatings of viscous liquid substance to opposite faces `of a movinglength of.sheet material,- such e. g. as paper, cloth, or

upon the coating substanceand sheet material which governs uniformity ofthe respective applied coatings, and deposit thereof concentric to thethreads of cloth material, when the sheet material operated upon is of`such character.

Other objects of this invention, not at this time more particularlyenumerated, will be understood .from the following detailed descriptionthereof.

and

dii

are forced or impressed upon the opposite faces of the material in asingle operation.

Another object of the invention is to provide substantially'simultaneously operative "opposed An illustrative embodiment of thisinvention is shown in the accompanying drawings, in which:

Fig. lis a side elevational view of apparatus according to thisinvention adapted to carry out coating operations under the principlesthereof; Fig. 2 is a plan view of the same; 3 is a transverse verticalsection, taken on line 3-3 in Fig. 2, but drawn on an enlarged scale;and Fig. d is a diagrammatic view showing the vertical F.llatter-w-illreliiinnate occurrence of horizontal or\\ offset relation ofthel coating bars of the appa# ratus. i Similar characters of referenceare employed in the above described views, to indicate correspondingparts.

One form of apparatussuitable to perform the method of coating sheetmaterial according to4 this invention, as shown intheaccompanyingdrawings, comprises, a supporting frame-work I0, inconnection with which is supported, to extend transversely from side toside thereof,a suitably shaped dipping reservoir or tank II to contain asupply of the selected viscous liquid substance S with which the facesof running lengths oi sheet material M lare desired to` be coated.

Rotatably mounted withinsaid reservoir ortank'lhandsoastobesubmergedinthe content of the` coating substance S-contained therein, is a dipping roll or drum I2 over which runs thesheet material MI to be whereby said material is passed through thecoating substancesoastopickupthicklayers I andi-'of the latter upon ifsopposite faces, to be carried upwardly therewith by -the emerging risingcourse of'saidmaterial M.

weight body of or other suitable material which is preferably but not ofcircular crosssectional shape. The external stu-faces of the coatingbars are given a smooth and prefer- Suitable means are provided forconducting thesheetmaterialllfromasupplyroll there oftoandintosaiddlppingreservoirortank Il. `This means is subject towidedvyom `form. arrangement and 4'relitti of its detail -agencieaIllustx'ativ'e"t/l1ereof,'the same. as

shown,eomp/rises, bearing bracket means I l for /supporting the shaft orspindle Il upon which A saidsupplyroil N is rotatably mounted; said sbearing'bracketmeans llbeingsecuredtoand so as to project from an end-ofthe framework Il opposite to that adjacent te which said dipping-reservoir or tank Il is located. suitably. andA preferably adjustably,mounted across the end of said framework Il adjacent to the supply rollIl is a guide roller Il over which the sheet material M is led fromthesupply roll to tensioning rollers fromwhence it passes downwardly intothe dipassociated supporting carrier member, are spacer ping reservoiror tank il and around thedipping .roll-or drum I2which is submergedwithin the content 4ofV the latter. Said tensioning rollers comprise'arearward roller Il and a forward roller Il. the respective shafts I Iand 20.01 which are journaied in suitable bearing supports 2l carried bystandard brackets 22 which are afiixed 35 to and which rise from thesides of the framework Il. The tensioning rollers 'are so relativelythat the forward roiler Il is somewhat elevated above the rearwardroller Il,- so

latter and thence upwardly to and over the former. Braid forward. rollerit overhangs the open topofthedippingreservoirortank I|,sothat that thesheet material Mbeneath the40withsaid the sheet material M .extendstherefrom downwardly into the interior ofthe latter -t andaroundthedippingrollordrum i2.andsoasto be submerged in and movedthrough the coating substance S contained in said dipping reservoir ortank Il. In order to prevent wrlnkling of the sheet' material M and tospread the same smoothcollars 34 which desirably offset the former fromthe latter. The' free end portions of said coupling studs 33 arescrew-threaded for the reception of fastening nuts Il whereby theelements of .the

, assembly are-secured together in operative as.

sembled relation.

one of :ne mung bars, as an, wgetherwaag/ v its carrier member-32 isimmovably supported by standards It which are afiixed to and rise fromthe sides of the framework III, and to which the endsofsaidcarrlermemberI2 areinturnafnxeci.` The'other coating bar, as Il, together with itscarrier member I2 is movably supported for yieldable movement relativeto the stationary coating bar ll'. whereby splices connecting joinedlengths of sheet material M may pass between the coating bars withoutstraining the same or A disturbing their adjusted operative spaced reiaftion. Tothisendupstandingcarrierarmsllare.

pivotally mounted or fulcrumed on the sides of 'the framework I0. to theupper free ends of which the ends of the carrier member 22 associatedbar Il are aflixed.' provided fo eldably urging said coating bar 3|toward -the coating bar 3o so as to normally retain the former in itsadjusted operative spaced rtuiation to the latter. In one illustrativeform of .-u L to urge the toward the coating bar 3l by gravitation ofweights 3l which are attached to the carrier arms by cables 39. Saidcables run ly for e"` over the tensioning` rollers Il-Il andthencethrough the dipping reservoir or tank II in such smoothly spread,unwrinkled condition, a transversely curved spreader bar 22 is providedin spaced relation to-and in advance of said tensioning rollers AI'l-I8.Said spreader bar isv supported by bearings carried by verticalstandards 2l which are aixedto and which rise from the sides of theframework Il. Disposed above the opentop of the dipping reservoir ortank Il is the means for applying the single, uniform coatings of thecoating substance S simultaneously to the opposite faces of the sheetmaterial M'which issues from said dipping reservoir or tank Il; the samecomprising a-pair'of coating bars 2l and 3|, together with novel meansfor operatively supporting and adjusting the same in spaced relation toprovide the intermediate orifice or gap through whichlthepreliminarilycoatedsheetmaterialll passes over pulleys 4l mounted onbearing brackets 4l amxed to the framework lli. whereby said weights 3lare suspended subject to operative gravitation.

by the coating bars to the'sheet material M movupon emerging from saiddipping reservoir or tankll. Y.

`Eachcoating width of themateriaildtobecoatedand eachbarisofaiengthexceedingthe.'

Adjustable means are provided for primarilyI predetermining the opposedoperative spaced relation of said coating bars III 3|. An illus'-trative form of this means, as own in the accompanying drawings,comprises, opposed cooperating stop lugs 42 with which opposed ends ofthe carrier members $2 are provided, and which, by abutment one upon theother, arrest the carrier members and their coating bars in positionnecessary to determine the desired operative spaced relation of thelatter. So that such spaced relation may be varied according to thethickness of coatings desired to be applied ing therebetween, one ofeach pair of opposed stop lugs l2 is provided with a longitudinallyadinstable stop stud 43 which is threaded thereinto for endwiseprojection therefrom and for engagement by the opposed stop lug.

The spacer collars 3l roughly predetermine the alignment of theopposedcoating bars 30 and 3| as supported by their carrier members 32. Said ma, mpamt1ve1y flexible and nght 75' coating bars beingrelatively nexibleas com- MESJJS areV means, as'shown in `i'zhe accompanying drawiacca-iss pared with their heavy and rigid carrier meml bers 32, a moreprecise and very delicately adinstable alignment of the coating'bars atlocal points throughout the lengths thereof may be attained by insertingshims M at desired pointsv between the spacer collars 3l and the carriermembers I2, thus not only relatively adjusting the coating bars toassure uniform desired spacing thereof at all points throughout theirlengths, but also permitting micrometric adjustment of any given localarea of a coating bar without. displacing or disturbing the adjustment Ythereof at any other area or section thereof.

'I'he relative setting of the coating bars 3l and 3l by the supportingmeans thereof is so effected that a carefully calculated vertical oifsetof one Gil relative to the other is provided when they occupy theircooperative laterally spaced apart positions. In the coating method ofthis invention, the thickness or vweight of the coatings is determinednot by thetension of the material M but .by the spacing of the coating'bars themselves.

' quired single coatings c-c of desired uniform r :zov

able manner. Qrdinarily after leaving the coating bars, the coatedmaterial will be caused to run through suitable drying apparatus and anyother treating means required or desired, and

thereafterwound or rolled up asfinished coated material. In operation,the -material pick-up on its opposite faces comparatively thick layersI---l'` of the coating substance S.l Aa the material M with the thusdeposited heavy layers i-l' of coating substance S passes between thecoating bars 3l-3l, equal pressure will be exerted simultaneously onopposite sides of the moving material M which floats. so to speak, inequilibrium between the layers I--I' which are thinned down and gaugedto produce vthe rethickness and weight, while at the same time theequilibrium: thus established assures that the coatings will lieconcentric to the threads of t more or less open weave or porous clothin cases It has been noticed, however, that horizontal or transversewave or waves in the material M is likely to occur, especially when thematerial is of soft finished cloth, such wave or waves causing heavypick-up of coating substance S on one or. the other side of the goods,resulting in applied coatings which are not concentric to the-threads ofthe cloth, especially of cloth of more or less open or porous weave. Forexample, settings of the coating bars are usually .of the order oftwerity-flve one-thousandths of an inch apart, whereasthe goods may be`from four to eight onethousandths of an inch in thickness. It will`therefore be obvious thateven at such closely spaced adjustment of thecoating bars, there is where lthe material M is of such character.y Theequalized pressure exerted by the opposed coating bars is exercised inaccord with'known physical laws of vcomponent forces. Due to thepredetermined oriilce or gap between the coating bars V-3| through whichthe coating substance S is caused to pass with the material M, saidcoating substance S is forced by the pressure induced by thetravelingmovement of the material M to simultaneously form, in oneoperation, upon opposite faces of said material, uniform single coatingsc-c' which are substantially matheplenty of roomfor horizontal ortransverse waves to occur. These waves are naturally notuniform orrecurrent, and may consequently occur at'any'point or area of thegoodsto the great impairment .of coating uniformity. To avoid. suchdetrimental conditions, one coating liar` (e. g. the coating bar ll) ispositioned slightly above the other (e. g. the coating bar Il), see Fig.4. The amountofthis slight offset is so calculated that a vertical lineA--A forms a common tangent 4to the opposed sides of the coat- Forexample, assuming the inch, the vertical offset D may be readilycalculated as approximately V4 of an inch. Some varlation from thetheory as thus exemplified is, of

course, permissible. It will be obvious that, with the coating bars thusarranged, the thickness of the coats c andgc' (see Fig. 3) will still begoverned by the lateral spacing C of the coating bars; the slight offsetrelation of the latter, which approximates a distance equal to thethickness of the material M, will permit a'corresponding ing bars lli-3|when the bars are spacedvapart f for the distance C. y coating-bars3B-,3i are 11/2 inches in diameter, y

and the relative spacing'tliereof at C is .025 of an offset or jog inthe path of travel of the material M which is sufficient to effect aslight tensioning of goods, at the point of passage thereof 'between thecoating bars, whereby all-horizontal or transverse waving is eliminatedwith'consequent avoidance of any local irregularities in the thicknessand weight of the applied coats c 1 and c. v

It will be understood that thetravel or move-5l yment of the material Mfrom the supply roll il to and through the dipping reservoir or tank Iland thence upwardly for passage between -the coating bars Il-i may beproduced in any .suitmatically exact in quantity.

Owing to the yieldably supported conditio of the coating bar 3i relativeto the stationary n coating bar ,should a thickened part of the materialM, such e. g. as would be produced by av splice joining lengths thereofinto a continuous run, pass between the 'coating bars, said coating barIl would readily yield to its passage and then quickly return to itsnormal relation to the coating bar 3l without risk of undue stress orstrain being applied to said coating bars or disturbance of thecarefully adjusted alignment thereof.

1t will be understood that various changes could be mede in the abovedesciibed tnstructions, and that widely different embodiments of thisinvention could be made without departing from the scope thereof asdefined in the following claims. `It is therefore intended that allmatter contained in the foregoing description or shown in theaccompanying drawings shall be interpreted as illustrative and not in alimiting sense.

Iclaimz i 1. In apparatus for the purposes described, means to applypreliminary facing layers of coating substancev to opposite faces ofmaterial operated upon, a pair of laterally opposed coating bars ofcircular cross-section spaced apart tti-,provide an intermediate orinceof predeter- M-as it passes 1 'through the-dippingreservoir or tank Ilwill 4 y s,aso,4ss

rier members for predetermining the operative spaced relation ot saidcoating bars.

2. Apparatus as deilned in claim l; including means for carrier memberand itscoating bar in stationary position. and means for movablysupporting the other carrier member and its coating bar including meansto yieldably hold the same in operative stopped spaced relation to saidilxed carrier member and its coating bar.

3. In apparatus for the purposes jdescribed,

means to apply preliminary facing' layers of 'an intermediate orifice ofpredetermined width through which the thus charged material lswhereby todetermine the thickness of nished coats applied thereto, rigid carriermen'i-v zo bersforeachcoatingbar,emchcoatingba'be-` ing comparativelynexible, means to 'adJustablysecureeachexiblecoatingbartoitsrigidcarrier member including meansspaced along the same to fiexionally adjust the bar for parallelalignment with the cooperating opposed coating bar, and opposedcooperative means connected with the respective ends oi' said rigidcarrier members for predetermining the operative I relation of saidcoating bars.

4. Apparatus as deiined in claim 3, including means for xing one carriermember and its coating bar in stationary position, and means for movablysupporting the other carrier member.

andvits coating bar including means to yieldably hold the same inoperative stopped spaced .relabar.

